I read them both. American Family Physician (AFP) provides a nice overview of the full range of family medicine topics in a way that lends itself to quick reference (helped by the fact that the full contents of the journal can be accessed online). Journal of Family Practice (JFP) is more evidence-based, and makes great fodder for journal club. Their Patient-Oriented Evidence that Matters (POEMs) feature is worth the subscription price all by itself.